Mortgage Servicing Assets - Schedule of Range and Weighted-Average of Significant Unobservable Inputs (Details) - Discounted cash flow - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Commercial Mortgage Backed Securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.00%	1.01%
Discount rate	8.34%	7.42%
Escrow earn rate	2.06%	0.94%
Loan assumption rate	0.00%	0.00%
Commercial Mortgage Backed Securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Expected defaults	2.00%	2.00%
Discount rate	10.32%	10.59%
Escrow earn rate	2.49%	1.22%
Loan assumption rate	1.64%	1.75%
Commercial Mortgage Backed Securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.12%	1.18%
Discount rate	9.52%	9.20%
Escrow earn rate	2.31%	1.10%
Loan assumption rate	1.29%	1.44%
Agency residential mortgage-backed securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Discount rate	7.50%	7.51%
Servicing cost	$ 62.00	$ 62.00
Prepayment speed	5.84%	10.55%
Agency residential mortgage-backed securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Discount rate	8.52%	8.63%
Servicing cost	$ 8,075	$ 4,375
Prepayment speed	59.51%	50.81%
Agency residential mortgage-backed securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Discount rate	7.53%	7.55%
Servicing cost	$ 67.46	$ 72.48
Prepayment speed	8.82%	12.82%

Interest rate used to account for mortgage loan at fair value upon assumption.

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- Definition

Servicing Assets And Servicing Liabilities At Fair Value, Assumptions Used To Estimate Fair Value, Escrow Earn Rate

+ References

No definition available.

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- Definition

Servicing Assets And Servicing Liabilities At Fair Value, Assumptions Used To Estimate Fair Value, Servicing Cost

+ References

No definition available.

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122596-111746

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- Definition

Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

+ References

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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